Thomas Edison at His Ore-Concentrating Works, circa 1897

Summary

During the 1890s, Thomas Edison launched a New Jersey mining operation to address an iron ore shortage. He designed rock-crushing technology and an electromagnetic ore separator to extract low-grade ore from crushed boulders. The final product -- a briquette made of powdered iron ore -- didn't do well commercially, especially after high-grade ore was discovered around Lake Superior. In 1899, Edison left the industry.

During the 1890s, Thomas Edison launched a New Jersey mining operation to address an iron ore shortage. He designed rock-crushing technology and an electromagnetic ore separator to extract low-grade ore from crushed boulders. The final product -- a briquette made of powdered iron ore -- didn't do well commercially, especially after high-grade ore was discovered around Lake Superior. In 1899, Edison left the industry.